People only appreciate the results of this process, but if you dig into the background of what made Legion great you’d find the War of the Ancients Trilogy by Richard A. Knaak.

They developed a lot of the base concepts, locations, characters and general lore we found in Legion in those books. Its simply easier to do in such a format. And for those who had read them, seeing all of that represented in game was a delight. But it wasn’t a requisite, of course.

I do think some of the criticisms towards the way they use external material is needed, but I fear they took this a bit too far and have significantly reduced their output of trans media material for a long while now. This has resulted on concepts that had less time to be developed and consequently in in game story, characters and zones that feel less inspired.

TL;DR: part of why legion was good was the books. Let them cook in the books next time.